EXAM #1: ISCHEMIC HEART DISEASE Flashcards
What is the definition of Coronary Atherosclerosis?
Fatty infiltration of the tunica intima of a coronary artery
*Remember, if you have atherosclerosis is one location, you probably have it in many
What are the modifiable risk factors for CAD?
HTN
Hypercholesteroloemia
Smoking
DM
What are the non-modifiable risk factors for CAD?
Major:
- Age (45 men/ 55 women)
- Gender
- Genetics/ family hx.
Minor:
- Chronic renal disease
- Obesity
- CRP
- Sedentary lifestyle
- Psychology
Outline the response to injury model for ASCVD?
1) Endothelial injury–>lipids leak into the tunica intima
2) Monocytes/ macrophages oxidize lipids and consume them and form foam cells
3) Growth factors cause smooth muscle cell infiltration into the intima and form foam cells
4) Healing and inflammation occurs forming the plaque
*Note that smooth muscle and macrophages can form “foam cells”
What are the four cell types the participate in forming the atherosclerotic plaque?
1) Endothelium
2) Smooth muscle cells
3) Macrophages
4) Platelets
What are the morphologic stages of atherosclerosis?
1) Fatty streak
2) Intimal thickening
3) Fibrous plaque
What are the complications associated with atherosclerotic plaques?
1) Calcification
2) Ulceration
3) Hemorrhage into the plaque
4) Thrombosis
What is the most common cause of death in DM?
Consequences of atherosclerosis
What is the definition of a positive family history of CAD?
- Male, first degree relative under 55
- Female, first degree relative under 65
How much does DM increase the risk of a hard CVD event?
20%
What is the definition of diabetic dyslipidemia?
- Smaller denser LDL particles with LDL near normal (worse than elevated LDL)
- Low HDL
- Elevated TG
What are the possible markers of metabolic syndrome?
1) Diabetic dyslipidemia
2) PAH
3) Central abdominal obesity
4) Insulin resistance
How much does cigarette smoking increase the risk of CAD?
2x
This is the leading cause of preventable death in the US
How much does stopping smoking reduce the risk of CAD?
- 1/2 the risk after 1 year
- Same as non-smoker after 5 years
How does smoking enhance atherosclerosis?
1) Hemodynamic stress
2) Endothelial injury
3) Lipid changes
4) Enhanced coagulability
5) Arrhythmogenesis
6) Hypoxia
How are the risk factors for atherosclerosis described?
Synergistic i.e. the total effect is more than simply the sum
What are the complications of CAD?
1) ACS
2) Sudden cardiac death
3) Dilated cardiomyopathy
4) A-fib/flutter
List the primary prevention practices for CAD.
1) Diet
2) Exercise
3) Weight-loss
4) Smoking cessation
List the secondary prevention practices for CAD?
In the patient WITH ASCVD, treat risk factors e.g.
- HTN
- Dyslipidemia
- DM
- Smoking cessation
- Exercise
- Weight
- Diet
What is the “sign” of prinzmetal angina on ECG?
ST elevation at rest
What are the three major determinants of myocardial oxygen demand?
1) HR
2) Contractility
3) Systolic wall tension
What is the differential diagnosis for chest pain?
1) Costochondritis
2) GI
3) Aortic dissection
4) Pericarditis
What is stable angina?
Chest pain that arises with exertion or emotional stress
What is unstable angina?
Chest pain that occurs at rest i.e. “angina decubitus”
or
- New onset
- Subjectively worse discomfort
If chest pressure lasts a few seconds, is this angina? What if onset is abrupt?
No
- Angina lasts minutes
- Onset is gradual, not acute
What are the classic mitigating and exacerbating factors for angina?
Exacerbating:
- Increased work
- Lying down*
Mitigating:
- Cessation of activity
- Medication (nitro)
*Increased preload= increased wall tension
What labs are part of the work-up for angina?
1) Lipid panel
2) CBC
3) Blood chemistry panel with electrolytes, BUN, creatinine
3) UA for protein, glucose…etc.
What is the utility of a stress test?
1) Diagnosis of atypical angina
2) Prognosis in patient with stable angina
When is a stress test NOT indicated?
Asymptomatic patient under 40
What drugs are used for a pharmacologic stress test?
1) Adenosine*
2) Dipyridamole*
3) Dobutamine
*Vasodilators, heart works harder to fill the dilated vessels
What are the indications of a positive stress test?
1) ST changes
2) Development of angina
3) VT
When is the diagnosis of angina certain with a stress test?
ST depression greater than 2mm
What causes irreversible injury to the myocardium?
- Depletion of high-energy phosphate bonds
- Catabolite accumulation
How do you reduce MI injury?
1) Increase supply
- Reperfusion
- Coronary vasodilation
2) Decreased demand
- Beta blockers
- Decrease BP
- Reduce preload
- Reduce circulating catecholamines
What is the MOA of nitrates in treating MI?
Venodilators that:
- Decrease preload
- Decrease LV size and LV wall tension
Coronary dilation
What is the MOA of beta-blockers in MI?
Decrease heart rate and contractility to decrease oxygen demand
Do beta-blockers have any effect on oxygen supply?
NO
What is the major MOA of Ca++ antagonists in MI?
Decreased afterload by vasodilating effect
